Lorin Latarro started rehearsals for her Broadway debut on a Monday, and that Friday, she took to the stage in Swing. As the substitute in the wickedly difficult principal role, she rehearsed with her dance partner just once, on the afternoon of their first performance.

That was in 2000, and the lead dancer in Swing had broken her heel. Latarro had auditioned for other roles in the show, getting to the final rounds, but hadn’t made the ultimate cut. She was a strong technician, though, and a quick study, and hadn’t been forgotten. Desperate to plug the hole left by the lead female dancer, producers called her in.

“It was crazy partnering,” Latarro recalls. “I was dancing with the swing champion of the world, and the show was difficult and taxing. But I learned so much.”

Since then, Latarro has proved that her first try wasn’t a fluke. Now performing in the Broadway revival of Guys and Dolls as a Hot Box Girl and as the understudy for the lead role of Miss Adelaide, Latarro has built one of the most solidly successful resumés on Broadway. She’s worked on 11 shows including Movin’ Out, Spamalot, Fosse, and A Chorus Line, where she was also an understudy for several roles. More than anything else, her success is a direct product of dedication and determination.

Growing up in northern New Jersey, Latarro took tap, jazz, and ballet classes at the New Jersey School of Ballet, hopping the bus into New York City whenever possible to take extra classes or catch a show. “I saw maybe 15 Broadway shows a year,” she recalls. “It was always something I wanted to do.”

But going to college was also on Latarro’s to-do list. Her parents valued academics; her brothers are both surgeons and her sister is a Harvard graduate with a Wharton MBA. So while her family took no issue with Latarro choosing an artistic route, she wanted her path to the stage to be paved with an academic education.

And so Juilliard became her goal. “I didn’t really know what Juilliard was,” she says, “but I was like, ‘I’m going to Juilliard.’ I ended up jumping on a bus to the audition and handwriting my application on the bus. My ballet training was good, but it wasn’t world-class. I think I got in on guts and sheer passion.”

At Juilliard, she trained with Benjamin Harkarvy, then head of the dance department. “He told me, ‘We love you, you’re great, your performance quality is amazing. But you need to take three ballet classes a day for your first year here, and we’ll see how it goes at the end.’ ”

Harkarvy instructed her to go home and do 100 tendus in a bathtub full of warm water every night. “Ben Harkarvy taught me to live my life as an artist,” she says.

Hector Zaraspe and Jirí Kylián, who served as a guest teacher for repertory classes during her first semester, were also major influences. Zaraspe taught her that it’s not all about the steps. “Some people are so concerned about their legs being at their ears and doing the steps correctly,” she says. “What I learned at Juilliard was about authenticity and passion and acting.”

Having also trained under former Paul Taylor dancer Linda Kent, Latarro tried her hand at a modern dance career after graduation. She performed briefly with the Martha Graham Dance Company and then with MOMIX. After a year and a half, though, Broadway beckoned. She had always wanted to give it a try, and besides, she couldn’t let her years of vocal training go to waste. She had always paid serious attention to her voice, even joining a girl group called Pajama Party during high school. So she auditioned for Swing, and after the skin-of-her-teeth Broadway debut, hasn’t strayed from the Great White Way since. “I’m happiest when I’m acting, singing, and dancing at the same time,” she says. “I haven’t taken a day off in 10 years, but it’s sort of who I am.”

Latarro still takes ballet classes twice a week at Steps on Broadway—usually with Nancy Bielski, but also with Gelsey Kirkland as of late—in addition to a weekly jazz class, two weekly vocal lessons (with Joan Lader), and an acting intensive. “She’s what I call ‘old school,’ like Chita Rivera,” says Guys and Dolls choreographer Sergio Trujillo. “The kind of dancer who comes in, warms up, and is ready to go. It’s a dying form. It’s about the respect for the art. She has high, high standards.”

Indeed, during rehearsals, Latarro wastes not a moment, practicing her penchés or dropping into a plank position for a round of pushups when not needed onstage. The rehearsal period for Guys and Dolls was remarkably short—five weeks instead of the usual seven. Because of the condensed prep time, Latarro and her fellow dancers could keep up their training only by squeezing in early-morning gym sessions or after-hours ballet classes. And that, of course, was on top of the marathon sessions with Trujillo and director Des McAnuff, who previously helmed Jersey Boys. “It was intense—Des and Sergio expect 100 percent brain capacity at all times,” Latarro says. “You’re dancing all day and you’re in three-and-a-half-inch heels, and they think very quickly and they expect you to, too.”

In performance, she’s all sharp hip thrusts in “A Bushel and a Peck,” endless extensions in “Take Back Your Mink,” and sultry salsa steps in “Havana.” Latarro believes her job as an ensemble dancer imposes varied responsibilities. As one of the six Hot Box Girls, she performs in strict unison. “It’s about us dancing together, and it’s a lot of fun because you’ve got the camaraderie of the women,” she says.

The cast includes some very high-profile dancers like John Selya, Tharp’s original Eddie in Movin’ Out. “This ensemble is incredible,” says Latarro. “They are all hugely talented performers; all have done principal roles.” That the show was mounted in the midst of the economic downturn simply upped the ante. “The audition was insane. The best dancers were there because they weren’t working. There were six callbacks. It was like winning the lottery.”

The commitment with which Latarro attacks her assignments, whether in the ensemble or a featured role, has impressed even the most seasoned Broadway pros. “I think she expects herself to be perfect at all three,” Trujillo says, meaning dancing, singing, and acting. “I see her get aggravated with herself.” It’s this perfectionism and dedication to the many dimensions of her craft that led Trujillo to pick her for his Guys and Dolls pre-production team. “I’d always wanted to work with her,” he says. “She’s smart and has choreographic aptitude.”

That aptitude has reared its head recently. Latarro choreographed Hansel and Gretel for PBS’s Live from Lincoln Center. She was assistant choreographer on the NBC show, "Grease, You’re the One that I Want," and choreographed work for several “Gypsy of the Year” evenings in addition to various Broadway benefits. And in 2008 she was selected by DanceBreak Foundation, the musical theater choreographers’ organization, as a rising choreographer by a board that included Jerry Mitchell and Stephen Flaherty.

So what’s next for this versatile artist? She’s hoping to choreograph a Broadway show. “I’ve learned something from every choreographer I’ve worked with,” she says. “I’ve done 11 great, fun shows. I’d love to do more work, but eventually I think all of these tools I’ve gathered lead to the role of being a choreographer.” Latarro knows that, especially in tough economic times, landing a choreographer role on a new show won’t be easy. But, she says, “I’m not interested in going to work and taking it easy. Some people love to do step-touch-and-smile and that’s fine, but that’s not how I get my work. I get my work when I get down to the nitty-gritty and get a little hard-core.”